1 /* 2 * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 /* 25 * @test 26 * @bug 4826774 27 * @summary Numerical tests for hexadecimal inputs to parseDouble, parseFloat 28 * @author Joseph D. Darcy 29 */ 30 31 32 import java.util.regex.*; 33 34 public class ParseHexFloatingPoint { 35 private ParseHexFloatingPoint(){} 36 37 public static final double infinityD = Double.POSITIVE_INFINITY; 38 public static final double NaND = Double.NaN; 39 40 static int test(String testName, String input, 41 double result, double expected) { 42 int failures =0; 43 44 if (Double.compare(result, expected) != 0 ) { 45 System.err.println("Failure for " + testName + 46 ": For input " + input + 47 " expected " + expected + 48 " got " + result + "."); 49 } 50 51 return failures; 52 } 53 54 static int testCase(String input, double expected) { 55 int failures =0; 56 57 58 // Try different combination of letter components 59 input = input.toLowerCase(java.util.Locale.US); 60 61 String [] suffices = {"", "f", "F", "d", "D"}; 62 String [] signs = {"", "-", "+"}; 63 64 for(int i = 0; i < 2; i++) { 65 String s1 = input; 66 if(i == 1) 67 s1 = s1.replace('x', 'X'); 68 69 for(int j = 0; j < 2; j++) { 70 String s2 = s1; 71 if(j == 1) 72 s2 = s2.replace('p', 'P'); 73 74 for(int k = 0; k < 2; k++) { 75 String s3 = s2; 76 if(k == 1) 77 s3 = upperCaseHex(s3); 78 79 80 for(int m = 0; m < suffices.length; m++) { 81 String s4 = s3 + suffices[m]; 82 83 84 for(int n = 0; n < signs.length; n++) { 85 String s5 = signs[n] + s4; 86 87 double result = Double.parseDouble(s5); 88 failures += test("Double.parseDouble", 89 s5, result, (signs[n].equals("-") ? 90 -expected: 91 expected)); 92 } 93 } 94 } 95 } 96 } 97 98 return failures; 99 } 100 101 static String upperCaseHex(String s) { 102 return s.replace('a', 'A').replace('b', 'B').replace('c', 'C'). 103 replace('d', 'D').replace('e','E').replace('f', 'F'); 104 } 105 106 /* 107 * Test easy and tricky double rounding cases. 108 */ 109 static int doubleTests() { 110 111 /* 112 * A String, double pair 113 */ 114 class PairSD { 115 public String s; 116 public double d; 117 PairSD(String s, double d) { 118 this.s = s; 119 this.d = d; 120 } 121 } 122 int failures = 0; 123 124 125 126 // Hex strings that convert to three; test basic functionality 127 // of significand and exponent shift adjusts along with the 128 // no-op of adding leading zeros. These cases don't exercise 129 // the rounding code. 130 String leadingZeros = "0x0000000000000000000"; 131 String [] threeTests = { 132 "0x.003p12", 133 "0x.006p11", 134 "0x.00cp10", 135 "0x.018p9", 136 137 "0x.3p4", 138 "0x.6p3", 139 "0x.cp2", 140 "0x1.8p1", 141 142 "0x3p0", 143 "0x6.0p-1", 144 "0xc.0p-2", 145 "0x18.0p-3", 146 147 "0x3000000p-24", 148 "0x3.0p0", 149 "0x3.000000p0", 150 }; 151 for(int i=0; i < threeTests.length; i++) { 152 String input = threeTests[i]; 153 failures += testCase(input, 3.0); 154 155 input.replaceFirst("^0x", leadingZeros); 156 failures += testCase(input, 3.0); 157 } 158 159 long bigExponents [] = { 160 2*Double.MAX_EXPONENT, 161 2*Double.MIN_EXPONENT, 162 163 (long)Integer.MAX_VALUE-1, 164 (long)Integer.MAX_VALUE, 165 (long)Integer.MAX_VALUE+1, 166 167 (long)Integer.MIN_VALUE-1, 168 (long)Integer.MIN_VALUE, 169 (long)Integer.MIN_VALUE+1, 170 171 Long.MAX_VALUE-1, 172 Long.MAX_VALUE, 173 174 Long.MIN_VALUE+1, 175 Long.MIN_VALUE, 176 }; 177 178 // Test zero significand with large exponents. 179 for(int i = 0; i < bigExponents.length; i++) { 180 failures += testCase("0x0.0p"+Long.toString(bigExponents[i]) , 0.0); 181 } 182 183 // Test nonzero significand with large exponents. 184 for(int i = 0; i < bigExponents.length; i++) { 185 long exponent = bigExponents[i]; 186 failures += testCase("0x10000.0p"+Long.toString(exponent) , 187 (exponent <0?0.0:infinityD)); 188 } 189 190 // Test significands with different lengths and bit patterns. 191 { 192 long signif = 0; 193 for(int i = 1; i <= 0xe; i++) { 194 signif = (signif <<4) | (long)i; 195 failures += testCase("0x"+Long.toHexString(signif)+"p0", signif); 196 } 197 } 198 199 PairSD [] testCases = { 200 new PairSD("0x0.0p0", 0.0/16.0), 201 new PairSD("0x0.1p0", 1.0/16.0), 202 new PairSD("0x0.2p0", 2.0/16.0), 203 new PairSD("0x0.3p0", 3.0/16.0), 204 new PairSD("0x0.4p0", 4.0/16.0), 205 new PairSD("0x0.5p0", 5.0/16.0), 206 new PairSD("0x0.6p0", 6.0/16.0), 207 new PairSD("0x0.7p0", 7.0/16.0), 208 new PairSD("0x0.8p0", 8.0/16.0), 209 new PairSD("0x0.9p0", 9.0/16.0), 210 new PairSD("0x0.ap0", 10.0/16.0), 211 new PairSD("0x0.bp0", 11.0/16.0), 212 new PairSD("0x0.cp0", 12.0/16.0), 213 new PairSD("0x0.dp0", 13.0/16.0), 214 new PairSD("0x0.ep0", 14.0/16.0), 215 new PairSD("0x0.fp0", 15.0/16.0), 216 217 // Half-way case between zero and MIN_VALUE rounds down to 218 // zero 219 new PairSD("0x1.0p-1075", 0.0), 220 221 // Slighly more than half-way case between zero and 222 // MIN_VALUES rounds up to zero. 223 new PairSD("0x1.1p-1075", Double.MIN_VALUE), 224 new PairSD("0x1.000000000001p-1075", Double.MIN_VALUE), 225 new PairSD("0x1.000000000000001p-1075", Double.MIN_VALUE), 226 227 // More subnormal rounding tests 228 new PairSD("0x0.fffffffffffff7fffffp-1022", Math.nextDown(Double.MIN_NORMAL)), 229 new PairSD("0x0.fffffffffffff8p-1022", Double.MIN_NORMAL), 230 new PairSD("0x0.fffffffffffff800000001p-1022",Double.MIN_NORMAL), 231 new PairSD("0x0.fffffffffffff80000000000000001p-1022",Double.MIN_NORMAL), 232 new PairSD("0x1.0p-1022", Double.MIN_NORMAL), 233 234 235 // Large value and overflow rounding tests 236 new PairSD("0x1.fffffffffffffp1023", Double.MAX_VALUE), 237 new PairSD("0x1.fffffffffffff0000000p1023", Double.MAX_VALUE), 238 new PairSD("0x1.fffffffffffff4p1023", Double.MAX_VALUE), 239 new PairSD("0x1.fffffffffffff7fffffp1023", Double.MAX_VALUE), 240 new PairSD("0x1.fffffffffffff8p1023", infinityD), 241 new PairSD("0x1.fffffffffffff8000001p1023", infinityD), 242 243 new PairSD("0x1.ffffffffffffep1023", Math.nextDown(Double.MAX_VALUE)), 244 new PairSD("0x1.ffffffffffffe0000p1023", Math.nextDown(Double.MAX_VALUE)), 245 new PairSD("0x1.ffffffffffffe8p1023", Math.nextDown(Double.MAX_VALUE)), 246 new PairSD("0x1.ffffffffffffe7p1023", Math.nextDown(Double.MAX_VALUE)), 247 new PairSD("0x1.ffffffffffffeffffffp1023", Double.MAX_VALUE), 248 new PairSD("0x1.ffffffffffffe8000001p1023", Double.MAX_VALUE), 249 }; 250 251 for (int i = 0; i < testCases.length; i++) { 252 failures += testCase(testCases[i].s,testCases[i].d); 253 } 254 255 failures += significandAlignmentTests(); 256 257 { 258 java.util.Random rand = new java.util.Random(); 259 // Consistency check; double => hexadecimal => double 260 // preserves the original value. 261 for(int i = 0; i < 1000; i++) { 262 double d = rand.nextDouble(); 263 failures += testCase(Double.toHexString(d), d); 264 } 265 } 266 267 return failures; 268 } 269 270 /* 271 * Verify rounding works the same regardless of how the 272 * significand is aligned on input. A useful extension could be 273 * to have this sort of test for strings near the overflow 274 * threshold. 275 */ 276 static int significandAlignmentTests() { 277 int failures = 0; 278 // baseSignif * 2^baseExp = nextDown(2.0) 279 long [] baseSignifs = { 280 0x1ffffffffffffe00L, 281 0x1fffffffffffff00L 282 }; 283 284 double [] answers = { 285 Math.nextDown(Math.nextDown(2.0)), 286 Math.nextDown(2.0), 287 2.0 288 }; 289 290 int baseExp = -60; 291 int count = 0; 292 for(int i = 0; i < 2; i++) { 293 for(long j = 0; j <= 0xfL; j++) { 294 for(long k = 0; k <= 8; k+= 4) { // k = {0, 4, 8} 295 long base = baseSignifs[i]; 296 long testValue = base | (j<<4) | k; 297 298 int offset = 0; 299 // Calculate when significand should be incremented 300 // see table 4.7 in Koren book 301 302 if ((base & 0x100L) == 0L ) { // lsb is 0 303 if ( (j >= 8L) && // round is 1 304 ((j & 0x7L) != 0 || k != 0 ) ) // sticky is 1 305 offset = 1; 306 } 307 else { // lsb is 1 308 if (j >= 8L) // round is 1 309 offset = 1; 310 } 311 312 double expected = answers[i+offset]; 313 314 for(int m = -2; m <= 3; m++) { 315 count ++; 316 317 // Form equal value string and evaluate it 318 String s = "0x" + 319 Long.toHexString((m >=0) ?(testValue<<m):(testValue>>(-m))) + 320 "p" + (baseExp - m); 321 322 failures += testCase(s, expected); 323 } 324 } 325 } 326 } 327 328 return failures; 329 } 330 331 332 /* 333 * Test tricky float rounding cases. The code which 334 * reads in a hex string converts the string to a double value. 335 * If a float value is needed, the double value is cast to float. 336 * However, the cast be itself not always guaranteed to return the 337 * right result since: 338 * 339 * 1. hex string => double can discard a sticky bit which would 340 * influence a direct hex string => float conversion. 341 * 342 * 2. hex string => double => float can have a rounding to double 343 * precision which results in a larger float value while a direct 344 * hex string => float conversion would not round up. 345 * 346 * This method includes tests of the latter two possibilities. 347 */ 348 static int floatTests(){ 349 int failures = 0; 350 351 /* 352 * A String, float pair 353 */ 354 class PairSD { 355 public String s; 356 public float f; 357 PairSD(String s, float f) { 358 this.s = s; 359 this.f = f; 360 } 361 } 362 363 String [][] roundingTestCases = { 364 // Target float value hard rouding version 365 366 {"0x1.000000p0", "0x1.0000000000001p0"}, 367 368 // Try some values that should round up to nextUp(1.0f) 369 {"0x1.000002p0", "0x1.0000010000001p0"}, 370 {"0x1.000002p0", "0x1.00000100000008p0"}, 371 {"0x1.000002p0", "0x1.0000010000000fp0"}, 372 {"0x1.000002p0", "0x1.00000100000001p0"}, 373 {"0x1.000002p0", "0x1.00000100000000000000000000000000000000001p0"}, 374 {"0x1.000002p0", "0x1.0000010000000fp0"}, 375 376 // Potential double rounding cases 377 {"0x1.000002p0", "0x1.000002fffffffp0"}, 378 {"0x1.000002p0", "0x1.000002fffffff8p0"}, 379 {"0x1.000002p0", "0x1.000002ffffffffp0"}, 380 381 {"0x1.000002p0", "0x1.000002ffff0ffp0"}, 382 {"0x1.000002p0", "0x1.000002ffff0ff8p0"}, 383 {"0x1.000002p0", "0x1.000002ffff0fffp0"}, 384 385 386 {"0x1.000000p0", "0x1.000000fffffffp0"}, 387 {"0x1.000000p0", "0x1.000000fffffff8p0"}, 388 {"0x1.000000p0", "0x1.000000ffffffffp0"}, 389 390 {"0x1.000000p0", "0x1.000000ffffffep0"}, 391 {"0x1.000000p0", "0x1.000000ffffffe8p0"}, 392 {"0x1.000000p0", "0x1.000000ffffffefp0"}, 393 394 // Float subnormal cases 395 {"0x0.000002p-126", "0x0.0000010000001p-126"}, 396 {"0x0.000002p-126", "0x0.00000100000000000001p-126"}, 397 398 {"0x0.000006p-126", "0x0.0000050000001p-126"}, 399 {"0x0.000006p-126", "0x0.00000500000000000001p-126"}, 400 401 {"0x0.0p-149", "0x0.7ffffffffffffffp-149"}, 402 {"0x1.0p-148", "0x1.3ffffffffffffffp-148"}, 403 {"0x1.cp-147", "0x1.bffffffffffffffp-147"}, 404 405 {"0x1.fffffcp-127", "0x1.fffffdffffffffp-127"}, 406 }; 407 408 String [] signs = {"", "-"}; 409 410 for(int i = 0; i < roundingTestCases.length; i++) { 411 for(int j = 0; j < signs.length; j++) { 412 String expectedIn = signs[j]+roundingTestCases[i][0]; 413 String resultIn = signs[j]+roundingTestCases[i][1]; 414 415 float expected = Float.parseFloat(expectedIn); 416 float result = Float.parseFloat(resultIn); 417 418 if( Float.compare(expected, result) != 0) { 419 failures += 1; 420 System.err.println("" + (i+1)); 421 System.err.println("Expected = " + Float.toHexString(expected)); 422 System.err.println("Rounded = " + Float.toHexString(result)); 423 System.err.println("Double = " + Double.toHexString(Double.parseDouble(resultIn))); 424 System.err.println("Input = " + resultIn); 425 System.err.println(""); 426 } 427 } 428 } 429 430 return failures; 431 } 432 433 public static void main(String argv[]) { 434 int failures = 0; 435 436 failures += doubleTests(); 437 failures += floatTests(); 438 439 if (failures != 0) { 440 throw new RuntimeException("" + failures + " failures while " + 441 "testing hexadecimal floating-point " + 442 "parsing."); 443 } 444 } 445 446 }